Hall effect and transverse magnetoresistance in a low-dimensional conductor HfTe5

Temperature dependence of Hall coefficient and transverse magnetoresistance of a low-dimensional conductor HfTe₅ with 1.5 wt. % Zr is reported for the first time up to 12 kOe in magnetic field. Hall coefficient changes sign from positive to negative at the temperature at which the peak of the resistivity has been observed. Temperature dependence of the transverse magnetoresistance has an anomaly. Two-carrier model has been proposed to explain the data qualitatively. These results suggest the change of the electronic structure associated with the charge density wave formation or some other kind of phase transition. Simple chemical bonding consideration shows that the carrier originates from p-like bands.